SACRAMENTO, Calif. (AP) â€” California's medical board and Department of Public Health have been asked to investigate 17 doctors and eight hospitals involved in the illegal sterilizations of female prison inmates, based on a critical state audit released Thursday.

The auditor's office recommended that those authorities investigate doctor and hospital practices in 39 cases where sterilizations were performed without inmates' lawful consent. At issue is whether the women were properly told of the nature and permanence of the procedure.

The cases will be referred to the department and medical board, said Liz Gransee, a spokeswoman for the federal court-appointed official who controls prison medical care. She said the investigations are confidential.

The 39 cases were among 144 between 2006 and last year in which inmates had their fallopian tubes tied or cut for the sole purpose of sterilizing them. Another 650 inmates had other medical procedures that could have resulted in sterilization.

Auditors found that nearly 30 percent of the tubal ligations and other sterilization procedures were performed without lawful consent.

In 27 cases, the inmate's doctor did not sign a required consent form saying the patient appeared mentally competent, understood the permanent effect and had waited at least 30 days and no more than 180 days to give the patient time to reconsider.

In 18 cases, there were potential violations in observing the waiting period. That included one case in which only 22 days elapsed between the time the inmate consented to the procedure and when the surgery was performed, and a second case in which 196 days passed.

Margarita Fernandez, a spokeswoman for the California State Auditor, said the 39 questionable sterilizations involved 17 doctors and eight hospitals. The sterilizations were performed by private doctors at hospitals outside the prisons, said Fernandez. Surgeries on prison inmates are typically performed at outside facilities.

The federal receiver's office took control of prison medical care in 2006, but said it didn't learn about the sterilization procedures until the legal advocacy group Justice Now raised the issue in January 2010. The receiver's office previously said it immediately took steps to stop the practice. Auditors found one sterilization since then, in 2011, and that tubal ligation was deemed to be medically necessary.

Justice Now did not immediately comment on the audit.

Auditors found one inmate who they determined might not have wanted to be sterilized. She consented to a tubal ligation in June 2008 but changed her mind three weeks later, and the consent form was returned to her. She signed a standard hospital consent form in September agreeing to both a cesarean section and tubal ligation, but without undergoing the 30-day waiting period that auditors said is required under state law to give patients "time to consider this permanent and life-changing decision."

State Sen. Hannah-Beth Jackson said she found it shocking that nearly 30 percent of the procedures were performed without obtaining proper consent. Jackson, D-Santa Barbara, is the author of SB1135, which would bar the state's prisons and jails from sterilizing inmates for the purpose of birth control.

"Clearly this demonstrates a real systemic problem that frankly implicates the entire culture and further demonstrates the need for my legislation," she said. Her bill passed the Senate last month, 36-0, and is awaiting consideration in the Assembly.

She fears that inmates may feel pressure to have the sterilizations, a topic that was not part of the auditor's review.

"The experience in and of itself is extraordinarily coercive," Jackson said of obtaining health care behind bars. "It's very difficult for a woman to exercise her free will under those circumstances."

Auditors found the receiver's office failed to make sure its own staff obtained necessary approvals from inmates and from two medical procedure review committees before inmates were sterilized. They recommended that the federal receiver adopt better procedures to monitor its own medical staff and medical providers who work under contract with the state. That includes improving medical record-keeping and making sure inmates give their informed consent to medical procedures.

"We are glad to see that our efforts to stop the practice have been successful," Gransee said, though she said the receiver's office will work with auditors "to improve our process further."

Letters to the medical board and public health department asking to transfer the cases were sent Wednesday, she said, and neither the board nor department commented.

The issue surfaced after the Center for Investigative Reporting found that doctors sterilized the nearly 150 female inmates without proper state approval over five years.

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